Tap hole drill

ABSTRACT

A taphole boring machine serving two tapholes includes a support structure, a mount and a suspension device of which the mount is secured on the supporting structure and the suspension device has a tilting device for the mount with the suspension device further including a mechanism within a frame, a first drive and two connection points with a mechanism designed in such a way that a positively guided translation of two connection points in relation to the frame can be produced by a drive pulse of the first drive so that a connecting line through the two connection points remains parallel with itself during such movement.

The invention relates to a taphole drilling machine, in particular ataphole drilling machine to serve several tapholes on a shaft furnace.

BACKGROUND OF THE INVENTION

Modern blast furnaces usually have several tapholes. Each of thesetaholes is served by its own drilling machine. As an efficient tapholedrilling machine is relatively expensive, it would, of course, beinteresting for cost reasons to develop a machine which can be used forseveral adjacent tapholes at the same time.

A taphole drilling machine of this type was already described in DE-A-1962 953 in 1967. This machine comprises a fixed bracket and an arm, thefirst end of which can be swivelled about a first axis and is mounted inthe fixed bracket. The arm, which can be swivelled by a drive from afirst operating position in front of the first taphole into a secondoperating position in front of the second taphole, carries at its freeend a vertical pivot on which a mount is mounted. A control rod isconnected by swivel joints to a fixed lever arm on the bracket and to acrank firmly seated on the pivot. These form a four-link swivel jointmechanism, in which a swivelling movement of the arm about the firstaxis produces a swivelling movement of the mount about the second axis.To allow adaptation of the angle of inclination of the drilling axis tothe respective taphole, the mount is connected by a horizontalswivelling joint to vertical pivots, and a tilting cylinder is arrangedbetween the mount and a flange secured rigidly to the vertical pivot. Toadapt the height of the drilling axis to the respective taphole on theother hand it is proposed that the mount be brought to different pointsof proximity to the taphole, i.e. to limit the swivelling movement ofthe arm. However, the result is that only very small differences inheight can be compensated, because firstly the swivelling movement ofthe arm determines the final position of the mount and, secondly, thedistance between the mount end and the taphole should preferably beidentical.

A rock drilling machine, as used in mines, for example, is known fromU.S. Pat. No. 3,349,975. This rock drilling machine has a parallelogrammechanism with a frame, three links and four joints, which permitsparallel displacement of a drill mount by means of a first pressurecylinder. A second pressure cylinder is connected between theparallelogram mechanism and the drill mount and permits tilting of thedrill mount. An additional rotary motor permits 360° rotation of theparallelogram mechanism about a horizontal axis. The aim of the deviceis to permit universal alignment of the drill mount via a hydrauliccontrol system in relation to a horizontal axis, so that the rockdrilling machine can drill several holes without having to berepositioned.

A taphole plugging machine, in which a mud gun is suspended by twoarticulated supporting links from a supporting structure, is known fromFR-A-2 604 511. A pressure cylinder permits swivelling of the mud gun ina vertical plane and thus firm contact with its nozzle against thetaphole. One of the two supporting links is longitudinally adjustable,so that the inclination of the mud gun can be adapted to the inclinationof a taphole.

There is a need for a taphole drilling machine which permits variationin the height and inclination of the drilling machine to serve twotapholes, which can approach two tapholes with a different height andinclination in an optimum manner.

SUMMARY OF THE INVENTION

In the taphole drilling machine according to the invention thesuspension device has a mechanism with a frame, a first drive and twoconnection points. The mechanism is designed in such a way that apositively guided translation of the two connection points in relationto the frame can be produced by a drive pulse of the first drive in sucha way that a connecting line through the two connection points remainsparallel with itself during this movement. A tilting device is providedwith a connection joint, a supporting joint and a second drive and isdesigned in such a way that the distance between the connection jointand the supporting joint is adjustable by a drive pulse of the seconddrive. It is mounted via the connection joint on a first of the twoconnection points of the mechanism. In a first embodiment of the tapholedrilling machine according to the invention the tilting device isconnected via its supporting joint to the mount, the second connectionpoint of the mechanism by a supporting joint to the mount and the frameto the supporting structure. In a second embodiment of the tapholedrilling machine according to the invention the tilting device isconnected via its supporting joint to the supporting structure, thesecond connection point of the mechanism by a supporting joint to thesupporting structure and the mount to the frame. In both forms ofconstruction the height of the mount can be adjusted via a single drivewithout changing the inclination of the mount.

According to the invention the mechanism is driven by a first pressurecylinder, which has a stroke limiting device with two independentlyadjustable strokes. The drill mount, which is raised into a restposition when approaching a taphole, can thus be lowered to the level oftwo tapholes at different heights in the operating position. The tiltingdevice is driven by a second pressure cylinder, which likewise has astroke limiting device with two independently adjustable strokes, sothat the drill mount, which is advantageously in a horizontal restposition when approaching a taphole, can be adapted to the inclinationof two tapholes with different inclination in the operating position.

In a preferred simple and space-saving embodiment the mechanismcomprises a frame and three links connected by four swivel joints A, B,C and D. In this mechanism the distance between joint A and joint Dcorresponds to the distance between joint B and joint C, the distancebetween joint A and joint B to the distance between joint D and joint Cand the distance between joint A and the supporting joint E of themechanism to the distance between joint B and the supporting joint F ofthe tilting device.

Alternatively the mechanism could also have two links arranged in anX-shape, which are connected in their centre by an additional swiveljoint. The frame and a third link are then each connected by a simpleswivel joint and a combined turning and sliding joint to the ends of thetwo links in an X-shaped arrangement, the geometrical arrangement ofthese swivel joints advantageously corresponding to the geometricalarrangement of the corner points of a rectangle. This form ofconstruction has the advantage that a pure vertical displacement of themount can be achieved without horizontal movement components. However,it is far more complicated in its construction as a result of theturning and sliding joint and requires substantially more space.

The mechanism is advantageously driven by a pressure cylinder but could,of course, also comprise a rotary drive of one of the links. Thepressure cylinder advantageously has a stroke limiting device with twoindependently adjustable strokes, so that the mount, which isadvantageously raised to a rest position when approaching a taphole, canbe lowered to the level of two tapholes of different height in theoperating position.

The tilting device is advantageously designed as a pantograph. Thesecond pressure cylinder can be mounted particularly easily on thispantograph. By opening and closing the pantograph the second pressurecylinder enables the distance between the connection joint and thesupporting joint of the tilting device to be adjusted. The pressurecylinder of the tilting device also advantageously has a stroke limitingdevice with two independently adjustable strokes, so that the mount,which is advantageously in a horizontal rest position when approaching ataphole, can be adapted to the inclination of two tapholes of differentinclination in the operating position.

The foregoing and additional objects and features of the invention willbecome apparent from the following description in which preferredembodiments have been set forth in detail in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partial view of a taphole drilling machine according to theinvention in a rest position;

FIG. 2 is a partial view of the taphole drilling machine in FIG. 1 in anoperating position;

FIG. 3 is a partial view of the taphole drilling machine in FIG. 1 in athird position;

FIG. 4 is a longitudinal section through an advantageous embodiment of apressure cylinder for a suspension device of a taphole drilling machineaccording to the invention, the main piston assuming a first endposition;

FIG. 5 is a longitudinal section as in FIG. 4, the main piston assuminga second end position.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A mount 10 (shown only in section) and a suspension device 12, by meansof which the mount 10 is mounted on a supporting structure 14, can beseen in FIGS. 1 to 3. For the sake of simplicity the supportingstructure 14 is shown only schematically in the figures. Such asupporting structure may comprise, for example, a rotatable arm, on thefree end of which the suspension device 12 is rotatable about an axis 16(indicated by a broken line). An advantageous embodiment of such asupporting structure 14 with an arm is described, for example, in thepatent applications of the applicant LU 88799 dated Aug. 1, 1996 and LU88782 dated Jun. 28, 1996, the entire disclosure of which is included byreference in the present application. In an alternative embodiment thesupporting structure 14 could, however, likewise comprise a car guidedby rails, which carries the suspension device 12.

The suspension device 12 is described in more detail below with the aidof FIG. 2. It comprises a flat, four-link mechanism with four swiveljoints. A first link 18 is designed as a mechanism frame and mounted onthe supporting structure 14. This first link 18 has two legs 20 and 22.The first leg 20 is connected via a joint A to a second link 24. Thelatter is L-shaped with a first arm 26 and a second arm 28, the joint Abeing arranged at the point of intersection of the two 25 arms 26 and28. The second leg 22 of the first link 18 is connected via a joint B toa third link 30. The latter is likewise L-shaped with a first arm 32 anda second arm 34, the joint B being arranged at the point of intersectionof the two arms 32 and 34. A fourth link 36, which is designed, forexample, as a rod, is connected via a joint D to the second arm 28 ofthe second link 24 and via a joint C to the second arm 34 of the thirdlink 30. The four links 18, 24, 30 and 36 designed in such a way thatthe distance between joint A and joint D corresponds to the distancebetween joint B and joint C, and the distance between joint A and jointB to the distance between joint D and joint C. The mechanism has twoconnection points E′ and F′. The connection point E′ is located on thefirst arm 26 of the second link 24 and a swivel joint E connecting themechanism to the mount 10 is assigned to it. The connection point F′ islocated on the first arm 32 of the third link 30.

The drive of the four-link mechanism described above is formed by apressure cylinder 38. The latter is pivoted with its first end on theframe 18 and with its second end on the second arm of the third link 30in the mechanism. In FIG. 2 the piston rod 40 of the pressure cylinder38 is retracted. By contrast the piston rod 40 of pressure cylinder 38is extended in FIG. 1. The extension of piston rod 40 caused rotation ofthe third link 30 about the joint B. This rotation was transmitted tothe second link 24 via the fourth link 36. By virtue of theabove-mentioned arrangement of joints A, B, C and D at the corner pointsof a parallelogram the angle of rotation of the second link 24 about thejoint A corresponds exactly to the angle of rotation of the third link30 about the joint B.

A tilting device 42 is connected via a connection joint F at theconnection point F′to the first arm 32 of the third link 30 and via asupporting joint G to the mount 10. The distance between joint A and thesupporting joint E corresponds to the distance between joint B and theconnection joint F, with the result that a drive pulse of the firstpressure cylinder 38 produces a positively guided translation of thesupporting joint E and the connection joint F in relation to the frame18, so that a hypothetical connecting line through the two connectionpoints E′ and F′ remains parallel with itself during this movement. Itfollows that the mount 10 can likewise be raised and lowered parallelwith itself by the pressure cylinder 38. The height of the drilling axiscan thus be fixed without changing the inclination of the mount 10 andthus the inclination of the drilling axis. It should be particularlyemphasized that the mechanism described above is of extremely compactconstruction and simultaneously introduces forces in the longitudinaldirection of the mount 10 relatively rigidly into the supportingstructure 14. The tilting device 42 is designed in such a way that thedistance between connection joint F and supporting joint G isadjustable. In the form of construction shown it comprises, for example,a two-link pantograph 44 with a joint H. A pressure cylinder 50 ispivoted at one end of the first link 46 and at the other end on thesecond link 48 of the pantograph 44 and thus enables the distancebetween joint F and joint G to be increased and reduced by opening andclosing the pantograph 44. The pressure cylinder 50 could, of course,also be connected directly, i.e. without pantograph 44, via a connectionjoint F to the first arm 32 of the third link 30 and via a supportingjoint G to the mount 10. However, the pressure cylinder 50 can beincorporated mechanically far more advantageously into the suspensiondevice 12 by means of the pantograph 44. Comparison of FIG. 2 with FIG.3 reveals that the distance between joints F and G was shortened byretraction of the piston rod of the pressure cylinder 50. Consequentlythe supporting joint G was raised in relation to the supporting joint E,so that the mount 10 is inclined forwards.

It should be noted that the same result is achieved if the mechanismframe is formed e.g. by the mount and the two supporting joints E and Gare connected to the supporting structure.

An advantageous embodiment of the two pressure cylinders 38 and 50 isdescribed with the aid of FIGS. 4 and 5. This is a pressure cylinder 100with a main piston 104, which is fitted into a cylinder chamber 102, andits stroke in the cylinder chamber 102 is adjustable via an attachedstroke limiting device. The latter comprises an auxiliary piston 106with a piston extension 108, which is sealingly introduced into thecylinder chamber 102. The auxiliary piston 106 seals a pressure chamber110, on which a pressure medium can act. A connection piece 112 issealingly led out of the pressure chamber 110 and has a thread 114 withtwo nuts 116 and 118 screwed on. In FIG. 4 the pressure chamber 110 ispressureless. The main piston 104 rests on the piston extension 108 andcan force the latter back as far as the stop of nut 116 on a clamp 120.It is clear that in this position the piston extension 108 projects onlyslightly into the cylinder chamber 102, so that the main piston strokecorresponds to almost the total length of the cylinder chamber 102.

In FIG. 5 the pressure chamber 110 is exposed to the same pressure asthe rear section of the cylinder chamber 102. The piston extension 108now projects substantially into the cylinder chamber 102 and limits thestroke of the main piston 104. As the cross-section of the pressurechamber 110 sealed by the auxiliary piston 106 is greater than thecross-section of cylinder chamber 102 sealed by the main piston 104, themain piston 104 can no longer force back the piston extension 108. Thesecond nut 118 enables the depth of penetration of the piston extension108 into the cylinder chamber 102 to be limited.

What is claimed is:
 1. A taphole drilling machine to serve two tapholescomprising: a supporting structure, a mount, a height adjustingmechanism and a vertical tilting device; wherein said height adjustingmechanism includes: a frame supported by said supporting structure, afirst pressure cylinder with an integrated stroke limiting device withtwo independently adjustable strokes; a first supporting jointconnecting said height adjusting mechanism to said mount and a firstconnection joint connecting said height adjusting mechanism to saidtilting device; and is designed in such a way that a stroke of saidfirst pressure cylinder produces a positively guided translation of saidfirst supporting joint and said first connection joint in relation tosaid frame, so that a connecting line through said first supportingjoint and said first connection joint remains parallel with itselfduring this movement; wherein said vertical tilting device includes: asecond pressure cylinder with an integrated stroke limiting device withtwo independently adjustable strokes; and a second supporting joint,connecting said tilting device to said mount; and and is designed insuch a way that the distance between said first connection joint andsaid second supporting joint is adjustable by a stroke of said pressurecylinder.
 2. The machine according to claim 1, wherein said heightadjusting mechanism is designed as a closed mechanism with a frame andthree links interconnected by four swivel joints, wherein: a firstswivel joint connects said frame to a first link; a second swivel jointconnects said frame to a second link; and a third swivel joint and afourth swivel joint connect a third link to said first link and saidsecond link, so as to close the mechanism.
 3. The machine according toclaim 2, wherein: the distance between said first swivel joint and saidfourth swivel joint corresponds to the distance between said secondswivel joint and said third swivel joint; the distance between saidfirst swivel joint and said second swivel joint corresponds to thedistance between said fourth swivel joint and said third swivel joint;and the distance between said first swivel joint and said firstsupporting joint corresponds to the distance between said second swiveljoint and said first connection joint.
 4. The machine according to claim3, wherein: said frame comprises a first connection leg carrying saidfirst swivel joint and a second connection leg carrying said secondswivel joint; said first link is L-shaped including a first arm carryingsaid fourth swivel joint and a second arm carrying said first supportingjoint, said first link being connected at the intersection of its firstand second arm via said first swivel joint to said frame; said firstlink is L-shaped including a first arm carrying said third swivel jointand a second arm carrying said first connection joint, said first linkbeing connected at the intersection of its first and second arm via saidsecond swivel joint to said frame; and said fourth link is rod-shapedand connects said third swivel joint to said fourth swivel joint.
 5. Themachine according to claim 1, wherein said tilting device is designed asa pantograph.
 6. The machine according to claim 1, wherein said strokelimiting device of said first or second pressure cylinder comprises anauxiliary piston for the stroke limitation.
 7. The machine according toclaim 6, wherein: said pressure cylinder has a cylinder chamber and amain piston that fits movably in said cylinder chamber; and saidauxiliary piston seals in said pressure cylinder a separate pressurechamber with a larger cross-section than said cylinder chamber and has apiston extension that is sealingly introduced into said cylinder chamberin order to limit the stroke of said main piston.
 8. The machineaccording to claim 7, wherein said auxiliary piston has a connectionpiece that is sealingly led outwards from said pressure chamber and hasa thread with two nuts screwed on for adjustable stroke limitation ofthe auxiliary piston.
 9. The machine according to claim 1, wherein thesupporting structure comprises an arm for swiveling the mount betweentwo tapholes.
 10. A taphole drilling machine to serve two tapholescomprising: a supporting structure, a mount, a height adjustingmechanism and a vertical tilting device; wherein said height adjustingmechanism includes: a frame supporting said mount, a first pressurecylinder with an integrated stroke limiting device with twoindependently adjustable strokes; a first supporting joint connectingsaid height adjusting mechanism to said supporting structure and a firstconnection joint connecting said height adjusting mechanism to saidtilting device; and is designed in such a way that a stroke of saidfirst pressure cylinder produces a positively guided translation of saidfirst supporting joint and said first connection joint in relation tosaid frame, so that a connecting line through said first supportingjoint and said first connection joint remains parallel with itselfduring this movement; wherein said vertical tilting device includes: asecond pressure cylinder with an integrated stroke limiting device withtwo independently adjustable strokes; and a second supporting joint,connecting said tilting device to said supporting structure; and and isdesigned in such a way that the distance between said first connectionjoint and said second supporting joint is adjustable by a stroke of saidpressure cylinder.
 11. The machine according to claim 10, wherein saidheight adjusting mechanism is designed as a closed mechanism with aframe and three links interconnected by four swivel joints, wherein: afirst swivel joint connects said frame to a first link; a second swiveljoint connects said frame to a second link; and a third swivel joint anda fourth swivel joint connect a third link to said first link and saidsecond link, so as to close the mechanism.
 12. The machine according toclaim 11, wherein: the distance between said first swivel joint and saidfourth swivel joint corresponds to the distance between said secondswivel joint and said third swivel joint; the distance between saidfirst swivel joint and said second swivel joint corresponds to thedistance between said fourth swivel joint and said third swivel joint;and the distance between said first swivel joint and said firstsupporting joint corresponds to the distance between said second swiveljoint and said first connection joint.
 13. The machine according toclaim 12, wherein: said frame comprises a first connection leg carryingsaid first swivel joint and a second connection leg carrying said secondswivel joint; said first link is L-shaped including a first arm carryingsaid fourth swivel joint and a second arm carrying said first supportingjoint, said first link being connected at the intersection of its firstand second arm via said first swivel joint to said frame; said firstlink is L-shaped including a first arm carrying said third swivel jointand a second arm carrying said first connection joint, said first linkbeing connected at the intersection of its first and second arm via saidsecond swivel joint to said frame; and said fourth link is rod-shapedand connects said third swivel joint to said fourth swivel joint. 14.The machine according to claim 10, wherein said tilting device isdesigned as a pantograph.
 15. The machine according to claim 10, whereinsaid stroke limiting device of said first or second pressure cylindercomprises an auxiliary piston for the stroke limitation.
 16. The machineaccording to claim 15, wherein: said pressure cylinder has a cylinderchamber and a main piston that fits movably in said cylinder chamber;and said auxiliary piston seals in said pressure cylinder a separatepressure chamber with a larger cross-section than the cylinder chamberand has a piston extension that is sealingly introduced into saidcylinder chamber in order to limit the stroke of said main piston. 17.The machine according to claim 16, wherein said auxiliary piston has aconnection piece that is sealingly led outwards from said pressurechamber and has a thread with two nuts screwed on for adjustable strokelimitation of the auxiliary piston.
 18. The machine according to claim10, wherein said supporting structure comprises an arm for swiveling themount between two tapholes.